Re: [PHP-DEV] Memory warning hook
One should try ext/memtrack http://pecl.php.net/package/memtrack Also ext/memprof https://github.com/arnaud-lb/php-memory-profiler/ Julien.Pauli On Tue, Mar 5, 2013 at 9:14 PM, nat...@starin.biz wrote: This is not the same at all. When are you going to run this code? Memory allocations happen all the time. What Nathan asked for is an event that is triggered when the memory consumption reaches a threshold. However, there is a different solution, which is better IMHO in the case of caches: weak references. A weak reference automatically frees the memory of the object, when the memory is needed. http://php.net/manual/en/book.weakref.php. Having said that, none of these solutions scale up to multiple servers. This is why shared cache systems like memcached are recommended. I agree this probably is a good solution and I personally do use it along with shared memory tools, however there may be cases where the dev may gain more benefit from having a memory-warning installable trigger in place. This would allow things like allowing the dev to release certain cache objects before others or something completely different that I have not thought of yet. Running the GC is most likely faster than most cleanup routines a user could run, also usually there is not that much stuff cached in PHP scripts. If a PHP script has tons of data, which it can easily throw away, in memory this sounds like a smell of an bad architecture. Cache cache-worthy stuff in memcache or such and fetch only the data you need. Also: What should happen if the system runs out of memory while doing the cleanup? Anything sane doesn't sound good either. Yes running the GC is much faster except they are two completely different processes... in my example the dev is keeping references to data for possible future use later on however it's not possible to know when to release these references so php's GC can collect them if the user does not implement something quite juristic like ticks or frequent function calls throughout a code base. You can use ticks :) http://php.net/control-structures.declare#control-structures.declare.ticks Yes Ticks are something useable (like said above) however I have found ticks are clunky, frequently shunned, and you'd be ticking for no reason most of the time. -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
[PHP-DEV] Memory warning hook
As PHP applications are turning into large frameworks one of the issues arriving is memory management. One of the issues is that many frameworks use sophisticated caching techniques to make accessing the same data quickly, this improves speed it is at the cost of memory. Often the developer knows these areas that cache and often times already have functions in place to clear out the cache, however in the case where PHP is approaching or exceeds memory limits PHP runs the GC then dies if it cannot allocate enough memory. If we implemented memory warning triggers or user function that will be called before the GC is executed which allows the user to try and free up some memory on their own. This hopefully would give more flexibility to allowing these advanced caching techniques but at the same time allow the cache to be cleared out in case memory is getting low. Thoughts? Thanks, Software Developer Nathan Bruer
Re: [PHP-DEV] Memory warning hook
Can't you do this already? memory_limit can be fetched via ini_read, and together with memory_get_usage you should be able to check for this sort of thing. Admittedly having to parse memory_limit (which can be in various units) is not perfect. On Tue, Mar 5, 2013 at 1:23 PM, nat...@starin.biz wrote: As PHP applications are turning into large frameworks one of the issues arriving is memory management. One of the issues is that many frameworks use sophisticated caching techniques to make accessing the same data quickly, this improves speed it is at the cost of memory. Often the developer knows these areas that cache and often times already have functions in place to clear out the cache, however in the case where PHP is approaching or exceeds memory limits PHP runs the GC then dies if it cannot allocate enough memory. If we implemented memory warning triggers or user function that will be called before the GC is executed which allows the user to try and free up some memory on their own. This hopefully would give more flexibility to allowing these advanced caching techniques but at the same time allow the cache to be cleared out in case memory is getting low. Thoughts? Thanks, Software Developer Nathan Bruer -- Tom Boutell P'unk Avenue 215 755 1330 punkave.com window.punkave.com -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Memory warning hook
On Tue, 2013-03-05 at 12:23 -0600, nat...@starin.biz wrote: As PHP applications are turning into large frameworks one of the issues arriving is memory management. One of the issues is that many frameworks use sophisticated caching techniques to make accessing the same data quickly, this improves speed it is at the cost of memory. Often the developer knows these areas that cache and often times already have functions in place to clear out the cache, however in the case where PHP is approaching or exceeds memory limits PHP runs the GC then dies if it cannot allocate enough memory. If we implemented memory warning triggers or user function that will be called before the GC is executed which allows the user to try and free up some memory on their own. This hopefully would give more flexibility to allowing these advanced caching techniques but at the same time allow the cache to be cleared out in case memory is getting low. Running the GC is most likely faster than most cleanup routines a user could run, also usually there is not that much stuff cached in PHP scripts. If a PHP script has tons of data, which it can easily throw away, in memory this sounds like a smell of an bad architecture. Cache cache-worthy stuff in memcache or such and fetch only the data you need. Also: What should happen if the system runs out of memory while doing the cleanup? Anything sane doesn't sound good either. johannes -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Memory warning hook
2013/3/5 Tom Boutell t...@punkave.com Can't you do this already? memory_limit can be fetched via ini_read, and together with memory_get_usage you should be able to check for this sort of thing. Admittedly having to parse memory_limit (which can be in various units) is not perfect. This is not the same at all. When are you going to run this code? Memory allocations happen all the time. What Nathan asked for is an event that is triggered when the memory consumption reaches a threshold. However, there is a different solution, which is better IMHO in the case of caches: weak references. A weak reference automatically frees the memory of the object, when the memory is needed. http://php.net/manual/en/book.weakref.php. Having said that, none of these solutions scale up to multiple servers. This is why shared cache systems like memcached are recommended. On Tue, Mar 5, 2013 at 1:23 PM, nat...@starin.biz wrote: As PHP applications are turning into large frameworks one of the issues arriving is memory management. One of the issues is that many frameworks use sophisticated caching techniques to make accessing the same data quickly, this improves speed it is at the cost of memory. Often the developer knows these areas that cache and often times already have functions in place to clear out the cache, however in the case where PHP is approaching or exceeds memory limits PHP runs the GC then dies if it cannot allocate enough memory. If we implemented memory warning triggers or user function that will be called before the GC is executed which allows the user to try and free up some memory on their own. This hopefully would give more flexibility to allowing these advanced caching techniques but at the same time allow the cache to be cleared out in case memory is getting low. Thoughts? Thanks, Software Developer Nathan Bruer -- Tom Boutell P'unk Avenue 215 755 1330 punkave.com window.punkave.com -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php Lazare INEPOLOGLOU Ingénieur Logiciel
Re: [PHP-DEV] Memory warning hook
2013/3/5 Lazare Inepologlou linep...@gmail.com 2013/3/5 Tom Boutell t...@punkave.com Can't you do this already? memory_limit can be fetched via ini_read, and together with memory_get_usage you should be able to check for this sort of thing. Admittedly having to parse memory_limit (which can be in various units) is not perfect. This is not the same at all. When are you going to run this code? Memory allocations happen all the time. What Nathan asked for is an event that is triggered when the memory consumption reaches a threshold. You can use ticks :) http://php.net/control-structures.declare#control-structures.declare.ticks However, there is a different solution, which is better IMHO in the case of caches: weak references. A weak reference automatically frees the memory of the object, when the memory is needed. http://php.net/manual/en/book.weakref.php. Having said that, none of these solutions scale up to multiple servers. This is why shared cache systems like memcached are recommended. Well, maybe I don't understand, what you are trying to tell, but if you run out of memory, this of course only affects one server on its own. On Tue, Mar 5, 2013 at 1:23 PM, nat...@starin.biz wrote: As PHP applications are turning into large frameworks one of the issues arriving is memory management. One of the issues is that many frameworks use sophisticated caching techniques to make accessing the same data quickly, this improves speed it is at the cost of memory. Often the developer knows these areas that cache and often times already have functions in place to clear out the cache, however in the case where PHP is approaching or exceeds memory limits PHP runs the GC then dies if it cannot allocate enough memory. If we implemented memory warning triggers or user function that will be called before the GC is executed which allows the user to try and free up some memory on their own. This hopefully would give more flexibility to allowing these advanced caching techniques but at the same time allow the cache to be cleared out in case memory is getting low. Thoughts? Thanks, Software Developer Nathan Bruer -- Tom Boutell P'unk Avenue 215 755 1330 punkave.com window.punkave.com -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php Lazare INEPOLOGLOU Ingénieur Logiciel -- github.com/KingCrunch
RE: [PHP-DEV] Memory warning hook
This is not the same at all. When are you going to run this code? Memory allocations happen all the time. What Nathan asked for is an event that is triggered when the memory consumption reaches a threshold. However, there is a different solution, which is better IMHO in the case of caches: weak references. A weak reference automatically frees the memory of the object, when the memory is needed. http://php.net/manual/en/book.weakref.php. Having said that, none of these solutions scale up to multiple servers. This is why shared cache systems like memcached are recommended. I agree this probably is a good solution and I personally do use it along with shared memory tools, however there may be cases where the dev may gain more benefit from having a memory-warning installable trigger in place. This would allow things like allowing the dev to release certain cache objects before others or something completely different that I have not thought of yet. Running the GC is most likely faster than most cleanup routines a user could run, also usually there is not that much stuff cached in PHP scripts. If a PHP script has tons of data, which it can easily throw away, in memory this sounds like a smell of an bad architecture. Cache cache-worthy stuff in memcache or such and fetch only the data you need. Also: What should happen if the system runs out of memory while doing the cleanup? Anything sane doesn't sound good either. Yes running the GC is much faster except they are two completely different processes... in my example the dev is keeping references to data for possible future use later on however it's not possible to know when to release these references so php's GC can collect them if the user does not implement something quite juristic like ticks or frequent function calls throughout a code base. You can use ticks :) http://php.net/control-structures.declare#control-structures.declare.ticks Yes Ticks are something useable (like said above) however I have found ticks are clunky, frequently shunned, and you'd be ticking for no reason most of the time. -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
